Field experiments have confirmed that today's wireless spectrum is under-utilized by the licensed users; by making vacant frequency bands available to opportunistic (known as secondary) users, cognitive radio promises to much better utilize the scarce wireless resources. Spectrum sensing is the act of determining whether a particular frequency band is vacant from its licensed users and is an important enabling premitive for cognitive radio. In this seminar, I will present one individual and one cooperative spectrum sensing techniques, both proposed by the ReCognize group at the Advanced Digital Sciences Center (ADSC).

The proposed individual spectrum sensing technique is more robust than energy and feature detection; additionally, the proposed technique is uniquely advantageous over other sensing protocols since it does not require any a priori field survey. Despite the many benefits of the proposed individual sensing protocol, fading and shadowing pose inevitable hurdles to the sensing operation. The research community proposes fusing sensing decisions from multiple sensors; thereby using diversity to overcome channel variance. At ADSC, we also propose a reliable cooperative sensing technique that is resilient to the false-reporting Sybil attack.

Biosketch:

Jerry Chiang is a postdoctoral researcher at the Advanced Digital Sciences Center under the ReCognize project. He obtained his doctoral degree in Electrical and Computer Engineering from the University of Illinois at Urbana-Champaign in 2011. In his thesis work, he focused on providing availability to the lower layers of wireless networks. He has coauthored more than a dozen peer-reviewed publications, and is broadly interested in the security issues at the lower layers of wireless and emerging networks.